Discharge lamp with light flashes



July 19, 1949. D. s. SCHREIBER 2,476,773

DISCHARGE LAMP WITH LIGHT FLASHES Filed May 2, 1946 Patented July 19,1949 UNETED STATES Laid??? PATENT OFFICE Dag Sigurdsson Schreiber,Lidingo, Sweden, assignor to Alitiehoiaget W Dan Bergman, Sodertalj e,Sweden Application May 2, 1946, Serial No. 666,573 In Sweden May 8, 19452 Claims.

The present invention relates to a device for generating light flashesin discharge lamps, especially neon lamps energised from a low voltagebattery with automatic interrupter. The figure in the accompanyingdrawing illustrates an embodiment of the invention by way of example. Inthe drawing l designates the neon lamp, which is connected in serieswith a condenser 2 and the secondary Winding of a transformer 2i. Ihecondenser may be short-circuited by a switch E. The primary winding ofthe trans former is connected to a current source 5, the current fromwhich is periodically interrupted by means of an automatic interrupterd.

At the opening as well as at the closing of the primary circuit avoltage is induced in the secondary winding of the transformer, but onlyat the opening thereof this voltage will normally be sufficiently highto ignite the neon lamp. In other words, the voltage impulses producedacross the secondary of the transformer by the opening of theinterrupters 4 are of a higher voltage value than the impulses producedupon closure of the primary circuit. The lamp l therefore serves toblock the flow of current in the secondary circuit oi the transformer 3in response to the voltage impulses induced in the secondary windingupon closure of the circuit making and breaking device t. As a resultthereof a pulsating direct current will flow through the lamp and chargethe condenser 2. When the voltage across the condenser has attained asuflicient value the lamp is ignited also at a closure of the primarycircuit, the energy stored in the condenser then being dischargedthrough the lamp in the form of a current in a direction opposite tothat of the charging current. During this discharge period the loadimpedance of the transformer is decreased, so that at the same time asthe condenser is discharged a much greater current impulse than thenormal one is delivered from the battery. During the discharge periodthe lamp will accordingly emit a considerably stronger light than duringthe charging period.

Having now described my invention, what I claim as new and desire tosecure by Letters Patent is:

1. Apparatus for producing light flashes comprising, a primary coil, asecondary coil arranged in inductive relationship with respect to theprimary coil, a source of direct current, a circuit connecting saidsource of current across the primary coil, a circuit making and breakingdevice for repeatedly opening and closing said circuit, a gaseousdischarge lamp, a condenser, a circuit connecting said gaseous dischargelamp and said condenser in series relationship across said secondarycoil, said gaseous discharge lamp having an ignition potential above thevoltage of the unidirectional pulse across the secondary coil duringclosure of said circuit making device and said gaseous discharge lamphaving an ignition potential lower than the voltage across the secondarycoil when said circuit making device opens whereby the condenserreceives successive charges from uni-directional pulses resulting fromrepeated openings only of said circuit making device so that a voltageis attained across the condenser which when added to the voltage of auni-directional pulse produced upon closure of said circuit makingdevice is sumcient to ignite said gaseous discharge lamp.

2. Apparatus for producing light flashes comprising, a primary coil, asecondary coil arranged in inductive relationship with respect to theprimary coil, a battery, a circuit connecting said battery across theprimary coil, a circuit making and breaking device including a singleperiodically operable element for repeatedly opening and closing saidcircuit, a gaseous discharge lamp, a condenser, a circuit connectingsaid gaseous discharge lamp and said condenser in series relationshipacross said secondary coil, said gaseous discharge lamp having anignition potential above the voltage of the uni-directional pulse acrossthe secondary coil during closure of said circuit making device and saidgaseous discharge lamp having an ignition potential lower than thevoltage across the secondary coil when said circuit making device openswhereby the condenser receives successive uni-directional pulsesresulting from repeated openings only of said circuit making device sothat a charge is accumulated by the condenser having a polaritycorresponding to the uni-directional pulses produced upon opening of thefirst circuit which when added to the voltage of one uni-directionalpulse produced upon closure of said circuit making device is sufficientto ignite said gaseous discharge lamp.

DAG SIGURDSSON SCI-IREIBER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,194,288 Aust Mar. 19, 1940FOREIGN PA'I'ENTS Number Country Date e88,142 Great Britain July 1, i938

